Polymer manhole base

ABSTRACT

A polymer manhole base may comprise a base portion having an upper surface. An annular sidewall may extend upward from the base portion and may circumscribe the upper surface. The manhole base may have a wastewater trough connecting a wastewater inlet and a wastewater outlet. An interior frame may correspond to the inlet or outlet.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 14/875,620, filed Oct. 5, 2015, which is a continuation of U.S. patent application Ser. No. 14/722,083, filed May 26, 2015, which is a continuation-in-part of U.S. patent application Ser. No. 14/023,313, filed Sep. 10, 2013, which is a continuation of U.S. patent application Ser. No. 13/844,487, filed Mar. 15, 2013, which are hereby incorporated by reference herein in their entireties, including but not limited to those portions that specifically appear hereinafter, the incorporation by reference being made with the following exception: In the event that any portion of the above-referenced applications are inconsistent with this application, this application supercedes the above-referenced applications.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

BACKGROUND

1. The Field of the Present Disclosure.

The present disclosure relates generally to wastewater systems, and more particularly, but not necessarily entirely, to manhole base structures.

2. Description of Related Art.

Components of wastewater systems may be formed from pre-cast concrete structures. For example, pre-cast concrete structures may include concrete pipes, box culverts, vaults, catch basins, and manhole assemblies. These pre-cast concrete structures may be formed off site and transported to a work site as needed. At the work site, the pre-cast concrete structures may be installed into wastewater systems, including sewage systems, as is known to one having ordinary skill in the art. Typically, the pre-cast concrete structures may be installed underground.

The pre-cast concrete structures used in wastewater systems are highly susceptible to microbial induced corrosion. Microbial induced corrosion is caused when hydrogen sulfide gas is released from wastewater. The gas is transformed into sulfuric acid by microbes present in the wastewater system. The sulfuric acid produced by the microbes may then quickly corrode the concrete structures by dissolving the cement binder used during the casting process. The corrosion caused by sulfuric acid may lead to severe damage to the pre-cast concrete structures.

Some attempts have been made in the prior art to reduce the damage caused by microbial induced corrosion. For example, one attempt at reducing microbial induced corrosion may include spraying a coating, such as an epoxy coating, on the pre-cast concrete structures. Disadvantageously, these coatings have been known to spall; thereby creating a pathway for the acid to eat away at the concrete. Other attempts to reduce the damage caused by microbial induced corrosion have included the use of plastic liners, which have also been demonstrated as not being completely effective.

The prior art is thus characterized by several disadvantages that are addressed by the present disclosure. The present disclosure minimizes, and in some aspects eliminates, the above-mentioned failures, and other problems, by utilizing the methods and structural features described herein.

The features and advantages of the present disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the present disclosure without undue experimentation. The features and advantages of the present disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of the disclosure will become apparent from a consideration of the subsequent detailed description presented in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of a polymer manhole base according to an embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of the polymer manhole base shown in FIG. 1;

FIG. 3 is a top view of the polymer manhole base shown in FIG. 1;

FIG. 4 is a top view of a polymer manhole base according to an embodiment of the present disclosure;

FIG. 5 is a top view of a polymer manhole base according to an embodiment of the present disclosure; and

FIG. 6 is a cross sectional view of the polymer manhole base shown in FIG. 3;

FIG.7 is a fragmentary view of the polymer manhole base shown in FIGS. 1 and 3.

FIG. 8 is an exploded, fragmentary view of a manhole assembly according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles in accordance with the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the disclosure as illustrated herein, which would normally occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the disclosure claimed.

In describing and claiming the present disclosure, the following terminology will be used in accordance with the definitions set out below. It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. As used herein, the terms “comprising,” “including,” “containing,” “characterized by,” “having,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps.

Pursuant to an embodiment of the present disclosure, applicant has discovered a polymer manhole base having a thin annular sidewall. In an embodiment, a thickness of the sidewall is defined by the difference between an outer diameter and an inner diameter of the sidewall. In an embodiment, the sidewall may have a thickness that is less than 1/12th of the inner diameter of the sidewall. Applicant's polymer manhole base may be formed of an resin and aggregate mixture.

Referring now to FIG. 1, there is depicted a polymer manhole base 100 according to an embodiment of the present disclosure. The manhole base 100 may be adapted for use in a municipal wastewater system. In an embodiment, the base 100 may comprise a solid base portion 101. In an embodiment, the base 100 may comprise an optional extended solid base portion 102 that provides additional stability and support to the base 100. The extended base portion 102 may comprise a bottommost surface 104 that may be adapted to rest on a bottom of an excavated hole.

Extending upwardly from the extended base portion 102 may be an annular sidewall 106 that terminates at an annular top surface 108. The annular sidewall wall 106 may comprise an outer surface 110 and an inner surface 112. The inner surface 112 may define an annular passageway 114 in the interior of the base 100. The passageway 114 may provide worker access to the interior of the manhole base 100.

The polymer manhole base 100 may further comprise an inlet 116 and an outlet 118 (outlet 118 is not explicitly visible in FIG. 1) for connecting the base 100 to a municipal wastewater system as is known to those having ordinary skill in the art. Inlet 116 may be referred to as wastewater inlet or wastewater inlet opening and outlet 118 may be referred to as wastewater outlet or wastewater outlet opening. A laterally extending flowpath 119 may pass into and from the wastewater inlet opening and extend to and through the wastewater outlet opening. The laterally extending flowpath 119 may define a channel through which wastewater may flow.

Referring now to FIG. 2, there is depicted a cross-section of the base 100 along the Section A-A shown in FIG. 1 where like reference numerals depict like components. The base 100 may have a base height, H. In an embodiment, the annular wall may define an inner diameter, ID, and an outer diameter, OD, as shown in FIG. 2. In an embodiment, the base height, H, may be between two feet and six feet. In an embodiment, the inner diameter, ID, may be between about 48 inches and 60 inches. In an embodiment, the outer diameter, OD, may be between about 48 inches and 64 inches.

A wall thickness, T, of the annular sidewall 106 may be defined by a difference between the outer diameter, OD, and the inner diameter, ID. In an embodiment, the wall thickness may be between one inch and three inches, or about 2 inches, or one-half inch or greater. In an embodiment, the wall thickness, T, may be less than 1/12th of the inner diameter, ID, of the annular sidewall 106.

Disposed at the bottom of the annular passageway 114 may be a surface 120. In an embodiment, the surface 120 may define a trough 122 that extends between the inlet 116 and a outlet 118. The trough 122 may provide a fluid pathway for wastewater between the inlet 116 and a outlet 118, and may define at least a lower portion of the flowpath 119. The surface 120 may define a bench portion 124 on either side of the trough 122. In an embodiment, the bench portion 124 may be sloped at an angle, θ. In an embodiment, the angle θ may vary from 0° and 45°. The trough 122

Extending radially inwardly from the inner surface 112 of the annular sidewall 106 may be an interior frame 130. Interior frame 130 may be a thickened wall area around wastewater inlet opening 116 or wastewater outlet opening 118. In an embodiment, interior frame 130 may surround at least a portion of the flowpath 119. The interior frame 130 forms part of an enclosed passage 131 that completely circumscribes a portion of the flowpath. Interior frame 130 may have an outer surface 136, and an inner surface 138.

In an embodiment, the base 100 may be cast by a continuous casting machine using polymer concrete. In an embodiment, the polymer concrete may comprise a polymer resin and aggregate mixture. In an embodiment, the aggregate may comprise a coarse aggregate and a fine aggregate. In an embodiment, the entire base 100 may be poured in one casting as a monolithic structure. The base 100 may be cast with or without the extended base 102. As seen in FIG. 2, extending from the surface 120 may be a plurality of anchors 126 that may be utilized to lift the base 100 using a lift mechanism. In an embodiment, the anchors 126 may comprise a hook or an eyelet.

Referring now to FIG. 3, where like reference numerals depict like components, in an embodiment the trough 122 may be substantially linear as it extends between the inlet 116 and the outlet 118. The interior frame 130 may be formed in the outer wall corresponding to at least one of the wastewater inlet 116 and the wastewater outlet 118. In an embodiment, base 100 may include an interior frame 130 at the wastewater inlet 116 and an interior frame 130 at the wastewater outlet 118. As further explained with reference to FIGS. 6 and 7, the interior frame 130 may be a thickened wall area around either the wastewater inlet 116 or the wastewater outlet 118.

Referring now to FIG. 4, there is depicted an embodiment of a base 100A with a trough 122A having a ninety-degree bend between an inlet 116A and an outlet 118A. FIG. 5 depicts an embodiment of a base 100B with a y-shaped trough 122B extending between a pair of inlets 116A and an outlet 118A. The inlet 116 may be connected to an upstream side of a municipal wastewater system and the outlet 118 may be connected to a downstream side of the municipal wastewater system. It will further be appreciated that either base 100A or base 100B may also comprise an interior frame as depicted in FIG. 3 corresponding to at least one of the inlets or outlets.

Referring now to FIGS. 6 and 7, where like reference numerals depict like components, base 100 may have an interior frame 130 corresponding to each of inlet 116 and outlet 118. Interior frame 130 may be formed in the sidewall 106 of base 100 and may be a thickened wall area around inlet 116 and outlet 118. In an embodiment, interior frame 130 may be integral or unitary with sidewall 106 such as would be formed in a single casting to form a monolithic structure. In another embodiment, interior frame 130 may be a separate structure that may abut sidewall 106 and may be attached or formed into sidewall 106 in any suitable manner, including with fasteners or through bonding such as with an adhesive.

In an embodiment, frame 130 may have a lateral surface 132, a medial surface 134, an outer surface 136, and an inner surface 138. Lateral surface 132 may correspond to inner surface 112 of base 100, and may abut or be formed integral with inner surface 112. Medial surface 134 may be a distal surface nearest a middle or center of base 100. Lateral surface 132 and medial surface 134 define a thickness, t, of interior frame 130. In an embodiment, the interior frame thickness, t, may be between 1/30th and ⅛th of the inner diameter, ID, of the annular sidewall 106, or may be between 1/24th and 1/10th of the inner diameter. In another embodiment, the interior frame thickness, t, may be between 2 and 8 inches. Further, the interior frame 130 may be disposed against the annular sidewall 106 and wherein the thickness of the frame, t, is at least two times the thickness, T, of the annular sidewall 106, and may also, if desired, be three times the thickness, T, of the annular sidewall 106, and if desired, may also be four times the thickness, T, of the annular sidewall 106, and if desired, may be any desired proportion of the thickness, T, of the annular sidewall 106, and certainly any fraction of said thickness, T, of the annular sidewall 106 such as 0.5 or 1.0 or 1.5 or 2.0 or 2.5 or 3.0 or 3.5 or 4.0 or 4.5 or 5.0, times said thickness, T, of the annular sidewall 106, or any fraction residing between any of the foregoing decimal proportions.

Inner surface 138 of interior frame 130 may correspond to trough 122, and may be coincident with trough 122 to form a continuous or smooth fluid pathway between inlet 116 and outlet 118. Outer surface 136 and inner surface 138 may define a height, h, of interior frame 130. Height, h, of interior frame 130 may correspond to the wall thickness, T, of annular sidewall 106. In an embodiment, interior frame height, h, may be between 0.5 and 5 times wall thickness, T. Alternatively, interior frame height, h, may correspond to the size of inlet 116 or outlet 118. Outer surface 136 and inner surface 138 may be annular, and interior frame height, h, may be constant or may vary between the annular surfaces. Alternatively, inner surface 138 may be annular and outer surface 136 may be polygonal, with interior frame height, h, varying at different locations along outer surface 136 and inner surface 138.

In an embodiment, interior frame 130 may be a thickened wall area around either inlet 116 or outlet 118, or both. Interior frame 130 may rise above surface 120 to surround the inlet or the outlet. In an embodiment, interior frame 130 may be integral or unitary with surface 120 such as would be formed in a single casting to form a monolithic structure. Interior frame 130 may alternatively be a separate structure that may abut surface 120 and may be attached or formed into surface 120 in any suitable manner, including with fasteners or through bonding such as with an adhesive.

Referring now to FIG. 8, there is depicted an exploded, fragmentary view of a manhole assembly 200 according to an embodiment of the present disclosure. The manhole assembly may comprise the base 100. The base 100 is adapted to be placed into an excavated hole. An inlet and an outlet of the base 100 is connected to a municipal wastewater system as is known to those having ordinary skill in the art.

Once the base 100 is placed into an excavated hole, one or more risers 202 are positioned onto the base 202. Next, a cone 204 may be positioned onto the riser 202. Disposed on the cone 204 may be a grade ring 206. An annular metal ring 208 and manhole cover 210 may be installed onto the grade ring 206. The hole into which the manhole assembly 200 is installed may then be backfilled. In an embodiment, the base 100, riser 202, cone 204, and grade ring 206 may be formed from a polymer resin and aggregate mixture.

Those having ordinary skill in the relevant art will appreciate the advantages provide by the features of the present disclosure. For example, it is a feature of the present disclosure to provide a polymer manhole base. Another feature of the present disclosure to provide such a base formed of polymer concrete.

In the foregoing Detailed Description, various features of the present disclosure are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description of the Disclosure by this reference, with each claim standing on its own as a separate embodiment of the present disclosure.

It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present disclosure. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of the present disclosure and the appended claims are intended to cover such modifications and arrangements. Thus, while the present disclosure has been shown in the drawings and described above with particularity and detail, it will be apparent to those of ordinary skill in the art that numerous modifications, including, but not limited to, variations in size, materials, shape, form, function and manner of operation, assembly and use may be made without departing from the principles and concepts set forth herein. 

1. A manhole base comprising: a base portion having an upper surface; an annular sidewall extending upward from the base portion and circumscribing the upper surface, said annular sidewall having a wastewater inlet opening and a wastewater outlet opening formed therein such that a laterally extending flowpath passes into and from said wastewater inlet opening and extends to and through said wastewater outlet opening; a wastewater trough formed in the upper surface of the base portion, the wastewater trough defining at least a lower portion of the flowpath and extending between the wastewater inlet and the wastewater outlet; and an interior frame extending radially inwardly from an inner surface of the sidewall, wherein the wastewater trough and the interior frame collectively surround at least a portion of the flowpath; wherein the annular sidewall comprises an inner diameter.
 2. The manhole base of claim 1, wherein the interior frame comprises a medial surface, a lateral surface, an inner surface, and an outer surface.
 3. The manhole base of claim 2, wherein the inner surface and outer surface of the interior frame are annular.
 4. The manhole base of claim 2, wherein the inner surface of the interior frame is annular and the outer surface of the interior frame is polygonal.
 5. The manhole base of claim 2, wherein the interior frame is disposed against the annular sidewall and wherein a thickness of said frame is at least two times a thickness of the annular sidewall.
 6. The manhole base of claim 1, wherein a thickness of the interior frame is between 1/30th and ⅛th of the inner diameter.
 7. The manhole base of claim 1, wherein a thickness of the interior frame is between 1/24th and 1/10th of the inner diameter.
 8. The manhole base of claim 1, wherein a thickness of the interior frame is between 2 and 8 inches.
 9. The manhole base of claim 1, wherein the manhole base comprises a resin and an aggregate mixture.
 10. The manhole base of claim 1, wherein a thickness of the annular sidewall is less than 1/12th of the inner diameter.
 11. The manhole base of claim 1, wherein the wastewater trough comprises a ninety-degree bend.
 12. The manhole base of claim 1, wherein the wastewater trough is y-shaped.
 13. The manhole base of claim 1, wherein the inner diameter of the annular sidewall is between 48 inches and 60 inches.
 14. The manhole base of claim 1, further comprising a bench formed on the upper surface.
 15. The manhole base of claim 14, wherein the bench comprises a slope of between 1 degree and 45 degrees.
 16. The manhole base of claim 1, wherein the manhole base comprises a monolithic structure. 17-42. (canceled)
 43. A manhole base comprising: a base portion having an upper surface; an annular sidewall extending upward from the base portion and circumscribing the upper surface, said annular sidewall having a wastewater inlet opening and a wastewater outlet opening formed therein such that a laterally extending flowpath passes into and from said wastewater inlet opening and extends to and through said wastewater outlet opening; a wastewater trough formed in the upper surface, the wastewater trough defining at least a lower portion of the flowpath and extending between the wastewater inlet and the wastewater outlet; and an interior frame extending radially inwardly from an inner surface of the sidewall and surrounding at least a portion of the flowpath; a bench formed on the upper surface; wherein the annular sidewall comprises an inner diameter; wherein a thickness of the annular sidewall is less than 1/12th of the inner diameter; wherein the manhole base comprises a resin and an aggregate mixture; wherein the interior frame comprises a medial surface, a lateral surface, an inner surface corresponding to the trough, and an outer surface; wherein a thickness of the interior frame is between 1/24th and 1/10th of the inner diameter; wherein the interior frame is disposed against the annular sidewall and wherein a thickness of said frame is at least two times a thickness of the annular sidewall; wherein the inner diameter of the annular sidewall is between 48 inches and 60 inches; wherein the bench comprises a slope of between 1 degree and 45 degrees; wherein the manhole base comprises a monolithic structure; wherein the frame forms part of an enclosed passage that completely circumscribes a portion of the flowpath.
 44. The manhole base of claim 5, wherein a thickness of said frame is at least three times a thickness of the annular sidewall.
 45. The manhole base of claim 5, wherein the frame forms part of an enclosed passage that completely circumscribes a portion of the flowpath.
 46. A manhole base comprising: a base portion having an upper surface; an annular sidewall extending upward from the base portion and circumscribing the upper surface, said annular sidewall having a wastewater inlet opening and a wastewater outlet opening formed therein; an interior frame extending radially inwardly from an inner surface of the sidewall; wherein the interior frame forms part of a rectangle having a hole formed therein, wherein no portion of the interior frame extends outwardly beyond a perimeter of the rectangle, and wherein the hole and one of the inlet opening and the outlet opening are contiguous.
 47. The manhole base of claim 46, wherein the interior frame forms part of an enclosed passage that completely circumscribes a portion of the flowpath.
 48. The manhole base of claim 46, wherein the interior frame comprises a medial surface, a lateral surface, an inner surface, and an outer surface.
 49. The manhole base of claim 48, wherein the inner surface and outer surface of the interior frame are circular.
 50. The manhole base of claim 48, wherein the inner surface of the interior frame is circular and the outer surface of the interior frame is polygonal.
 51. The manhole base of claim 48, wherein the interior frame is disposed against the annular sidewall and wherein a thickness of said frame is at least two times a thickness of the annular sidewall.
 52. The manhole base of claim 46, wherein the annular sidewall comprises an inner diameter and a thickness of the interior frame is between 1/30th and ⅛th of the inner diameter.
 53. The manhole base of claim 46, wherein a thickness of the interior frame is between 2 and 8 inches.
 54. The manhole base of claim 46, wherein the manhole base comprises a resin and an aggregate mixture.
 55. The manhole base of claim 46, wherein the annular sidewall comprises an inner diameter and a thickness of the annular sidewall is less than 1/12th of the inner diameter.
 56. The manhole base of claim 46, further comprising a wastewater trough formed in the upper surface, the wastewater trough defining at least a lower portion of the flowpath and extending between the wastewater inlet and the wastewater outlet; and.
 57. The manhole base of claim 46, wherein the annular sidewall comprises an inner diameter, wherein said inner diameter is between 48 inches and 60 inches.
 58. The manhole base of claim 46, wherein the manhole base comprises a monolithic structure.
 59. A method of forming an access to a municipal wastewater system, said method comprising: excavating a hole; placing a manhole base at a bottom of the hole, said manhole base comprising a base portion, an annular sidewall extending upward from the base portion, a wastewater inlet opening and a wastewater outlet opening formed in the annular sidewall, and a laterally extending flowpath extending from the inlet opening to the outlet opening; connecting an upstream side of the municipal wastewater system to the inlet opening and a downstream side of the municipal wastewater system to the outlet opening; placing one or more risers on top of the manhole base; placing a cone on top of the one or more risers; and backfilling the hole; wherein the manhole base further comprises a thickened wall area surrounding at least a portion of the laterally extending flowpath, said thickened wall area disposed around one of the inlet opening and the outlet opening, said thickened wall area further having a thickness that is greater than a thickness of the annular sidewall.
 60. The method of claim 59, wherein the thickened wall area of the manhole base comprises an interior frame extending radially inwardly from an inner surface of the sidewall and surrounding at least a portion of the flowpath.
 61. The method of claim 59, wherein the thickened wall area forms part of an enclosed passage that completely circumscribes a portion of the flowpath.
 62. The method of claim 59, wherein the thickened wall area forms part of a rectangle having a hole in the middle, wherein no portion of the thickened wall area extends outwardly beyond a perimeter of the rectangle, and the hole is concentric with one of the inlet opening and the outlet opening.
 63. The method of claim 61, wherein the interior frame comprises a medial surface, a lateral surface, an inner surface, and an outer surface
 64. The method of claim 63, wherein the inner surface and outer surface of the interior frame are circular.
 65. The method of claim 63, wherein the inner surface of the interior frame is circular and the outer surface of the interior frame is polygonal.
 66. The method of claim 59, wherein the annular sidewall comprises an inner diameter, and a thickness of the thickened wall area is between 1/30th and ⅛th of the inner diameter.
 67. The method of claim 59, wherein a thickness of the thickened wall area is between 2 and 8 inches.
 68. The method of claim 59, wherein the thickened wall area is formed in the annular sidewall.
 69. The method of claim 59, wherein the manhole base comprises a resin and an aggregate mixture.
 70. The method of claim 59, wherein the annular sidewall comprises an inner diameter and a thickness of the annular sidewall is less than 1/12th of the inner diameter.
 71. The method of claim 59, wherein the manhole base comprises a monolithic structure. 